which of the following describes a proportional relationship

ATI TEAS 7

TEAS Practice Math Test

1. Which of the following describes a proportional relationship?

A. Johnathan opens a savings account with an initial deposit of $150 and deposits $125 per month
B. Bruce pays his employees $12 per hour worked during the month of December, as well as a $250 bonus
C. Alvin pays $28 per month for his phone service plus $0.07 for each long-distance minute used
D. Kevin drives 65 miles per hour

Correct answer: A

Rationale: A proportional relationship is one in which two quantities vary directly with each other. In choice A, the amount deposited per month is directly proportional to the initial deposit. The relationship can be represented as y = 125x + 150, where x is the number of months and y is the total amount in the account. Choices B and C involve additional fixed amounts or variable costs that do not maintain a constant ratio, making them non-proportional relationships. Choice D refers to a constant speed of driving, which is not a proportional relationship as it does not involve varying quantities that change in direct proportion.

2. Chan receives a bonus from his job. He pays 30% in taxes, donates 30% to charity, and uses another 25% to pay off an old debt. He has $600 remaining. What was the total amount of Chan's bonus?

A. $3,000
B. $3,200
C. $3,600
D. $4,000

Correct answer: D

Rationale: Chan has used 30% + 30% + 25% = 85% of his bonus, which leaves 15% remaining. Since 15% of his bonus is $600, you can find the total bonus amount by dividing $600 by 15% (or multiplying by 100/15), which equals $4,000. Therefore, the correct answer is $4,000. The other choices are incorrect because they do not accurately represent the total remaining amount after the specified deductions.

3. Which number is larger, 0.5 or 1/3?

A. 0.5
B. 1/3
C. They are equal
D. Cannot be determined

Correct answer: A

Rationale: To compare 0.5 and 1/3, we can convert 0.5 to a fraction, which is 1/2. When comparing 1/2 and 1/3, we find that 1/2 is greater than 1/3. Therefore, 0.5 is larger than 1/3. Choice B is incorrect as 1/3 is smaller. Choice C is incorrect as the numbers are not equal. Choice D is incorrect as a clear comparison can be made.

4. What is a direct proportion? What is an inverse proportion?

A. Direct: Both quantities increase or decrease together; Inverse: When one quantity increases, the other decreases by the same factor
B. Direct: Both quantities decrease together; Inverse: When one quantity increases, the other increases
C. Direct: One quantity stays the same while the other increases; Inverse: Both quantities increase together
D. Direct: One quantity increases while the other decreases; Inverse: Both quantities decrease together

Correct answer: A

Rationale: In a direct proportion, both quantities increase or decrease together. This means that as one quantity goes up, the other also goes up, and vice versa. On the other hand, in an inverse proportion, when one quantity increases, the other decreases by the same factor. Therefore, choice A is correct as it accurately defines direct and inverse proportions. Choices B, C, and D are incorrect because they do not accurately describe the relationship between quantities in direct and inverse proportions.

5. In a class of 30 students, with 60% boys and 40% girls, how many girls are in the class?

A. 18 girls
B. 12 girls
C. 15 girls
D. 10 girls

Correct answer: B

Rationale: To find the number of girls in the class, we need to calculate 40% of the total number of students, which is 30. 40% of 30 is 0.40 * 30 = 12 girls. Therefore, there are 12 girls in the class. Choice A, 18 girls, is incorrect as it miscalculates the percentage. Choice C, 15 girls, is incorrect as it misrepresents the correct calculation. Choice D, 10 girls, is incorrect as it underestimates the number of girls in the class.